Ticket #44530: 44530.diff

wp-admin/includes/ajax-actions.php

@@ -1381 +1381 @@
                         wp_die( 1 );
                 }
 
+                // If meta key is empty, return error.
+                if ( isset( $_POST['metakeyinput'] ) && empty( $_POST['metakeyinput'] ) ) {
+                        wp_die( __( 'Please provide a custom field name.' ) );
+                }
+
                 // If the post is an autodraft, save the post as a draft and then attempt to save the meta.
                 if ( $post->post_status == 'auto-draft' ) {
                         $post_data                = array();